1) They winter on the California coast.
2) Monarch butterfly numbers are falling.
Across North America, the number of monarchs has dropped 27 percent in the last year alone, and by four-fifths since the 1990s. Habitat loss, especially in midwestern farm country, is a big reason. Farmers have plowed up most of the nation's milkweed patches to plant GMO soy and corn, much of it for ethanol fuels. But monarch caterpillars can only eat milkweed. And less food means fewer butterflies.
3) Environmentalists want legal protection for the butterfly.
The U.S. Fish and Wildlife Service has agreed to decide whether to list the monarch as a threatened species by 2019.
4) You can help by planting California native milkweeds.
Monarch caterpillars rely on milkweeds for food. Fortunately, many California native species are quite attractive in the garden — and unlike milkweeds from elsewhere, they've evolved to bloom right when California monarchs need them.
5) In the meantime, February is a great month to visit them on the coast.
They're more active now as mating begins. But don't wait too long: by the end of April, they'll have headed south.